32 PARASITIC AMCEB.E OF MAN. 



and pathogenic amoebae may inhabit the intestine of 

 man. 



Celli and Fiocca, in 1895, described no less than 

 six species of amoebae infesting the intestine of man 

 and named these organisms as follows: (1) Amoeba 

 spinosa; (2) Amoeba vermicularis; (3) Amoeba 

 diaphana; (4) Amoeba reticularis; (5) Amoeba 

 lobosa, variety guttata; (6) Amoeba lobosa, variety 

 oblonga. The names sufficiently describe the differ- 

 ential characteristics of these organisms, but they all 

 differed in size, one species, A. diaphana, measuring 

 only 0.5 to 2 microns in diameter. To one who has 

 studied these organisms the description of an amoeba 

 measuring but 0.5 micron in diameter may well be 

 viewed with suspicion, when we consider that such an 

 organism would be but little larger than the smallest 

 micrococcus. The largest amoebae described by Celli 

 and Fiocca did not exceed 10 microns in diameter, 

 which proves that these authors were not dealing 

 with true dysentery amoebae and it is more than prob- 

 able that many of the species described by them were 

 really stages in the development of the intestinal 

 flagellates. 



Casagrandi and Barbagallo were the first in- 

 vestigators to accurately describe the species of 

 amoeba occurring in the feces of healthy individuals 

 and now known as Entamoeba coli. They established 



